[OpenVINO backend] Support numpy.append (#20951)

* [OpenVINO backend] Support numpy.append

Signed-off-by: Lim, Kuan Xian <[email protected]>

* Remove NumpyDtype test_append_ from exclude list

Signed-off-by: Lim, Kuan Xian <[email protected]>

* Fix attribute error

Signed-off-by: Lim, Kuan Xian <[email protected]>

* Fix NumpyDtypeTest error

Signed-off-by: Lim, Kuan Xian <[email protected]>

* Update concat to append

Signed-off-by: Lim, Kuan Xian <[email protected]>

---------

Signed-off-by: Lim, Kuan Xian <[email protected]>

Author: kuanxian1

keras/src/backend/openvino/excluded_concrete_tests.txt

@@ -6,7 +6,6 @@ NumpyDtypeTest::test_absolute_bool
 NumpyDtypeTest::test_add_
 NumpyDtypeTest::test_all
 NumpyDtypeTest::test_any
-NumpyDtypeTest::test_append_
 NumpyDtypeTest::test_argmax
 NumpyDtypeTest::test_argmin
 NumpyDtypeTest::test_argpartition
@@ -159,7 +158,6 @@ NumpyOneInputOpsCorrectnessTest::test_unravel_index
 NumpyOneInputOpsCorrectnessTest::test_var
 NumpyOneInputOpsCorrectnessTest::test_vectorize
 NumpyOneInputOpsCorrectnessTest::test_vstack
-NumpyTwoInputOpsCorrectnessTest::test_append
 NumpyTwoInputOpsCorrectnessTest::test_bitwise_and
 NumpyTwoInputOpsCorrectnessTest::test_bitwise_left_shift
 NumpyTwoInputOpsCorrectnessTest::test_bitwise_or

keras/src/backend/openvino/numpy.py

@@ -191,7 +191,14 @@ def amin(x, axis=None, keepdims=False):
 
 
 def append(x1, x2, axis=None):
-    raise NotImplementedError("`append` is not supported with openvino backend")
+    x1, x2 = get_ov_output(x1), get_ov_output(x2)
+    x1, x2 = _align_operand_types(x1, x2, "append()")
+    if axis is None:
+        flatten_shape = ov_opset.constant([-1], Type.i32).output(0)
+        x1 = ov_opset.reshape(x1, flatten_shape, False).output(0)
+        x2 = ov_opset.reshape(x2, flatten_shape, False).output(0)
+        axis = 0
+    return OpenVINOKerasTensor(ov_opset.concat([x1, x2], axis).output(0))
 
 
 def arange(start, stop=None, step=None, dtype=None):